you make a promise you should keep it. A. ThoughB. UnlessC. Now thatD. Even if

问题补充：

you make a promise, you should keep it.

A. Though

B. Unless

C. Now that

D. Even if

答案：

A. Though

B. Unless

(答案→)C. Now that

D. Even if

解析：本题的含义是既然你做出承诺，你就应该遵守他，now that表示既然的意思，与题意较符合，故本题选C。